1. Field of the Invention
This invention relates to a portable tube squaring tool for enabling cutting of the ends of tubular workpieces to form square, bevel, undercut and other desired profiles on the ends of the workpieces.
2. Discussion of Related Art
Portable tube squaring tools are conventionally designed to rapidly secure a tubular workpiece relative to a cutting head carrying cutter bits so that the end of a tubular workpiece can be machined into an appropriate configuration quickly and efficiently in a repetitive manner. Repeatedly machining the ends of large numbers of different size tubular workpieces requires that the tool have a quick clamping and releasing arrangement for securing the workpieces to the tool and also requires that the workpiece holding device be adjustable to accommodate different diameter tubular workpieces.
A tube squaring tool constructed in accordance with the prior art is illustrated in U.S. Pat. No. 5,671,646 granted Sep. 30, 1997, as well as U.S. Pat. No. 4,739,682 granted Apr. 26, 1988. Still another example of a tube squaring tool is shown in U.S. Pat. No. 5,605,084 granted Feb. 25, 1997.
In tube squaring tools, the workpiece clamping device must be capable of repeatedly clamping tubular workpieces so that they are centered on the cutting axis of the tool which corresponds with the rotation axis of the tool cutting head. Also, exchanging the clamping devices to accommodate various size tubular workpieces must be carried out rapidly and efficiently. In accordance with the prior art, in particular, apparatus such as described in U.S. Pat. No. 5,671,646, the workpiece camping device utilizes a pair of saddle members that are each generally semi-circular in configuration and include arcuate inner surfaces that can be advanced towards each other to effectively clamp a tubular workpiece between the saddle members. Selective motion of one saddle member relative to the other saddle member to clamp a workpiece is achieved by a threaded actuator member that, when rotated, moves one saddle member relative to the other saddle member towards and away from the cutting axis of the tool.
In accordance with this prior art example, one of the saddle members is typically moved selectively by the clamping actuator, while the other saddle member is fixed in a mounting ring by another threaded member or members during operation of the tool. Replacing the saddle members involves disconnecting a plurality of threaded devices which are labor intensive and utilizes valuable time to effect changing of the saddle members.
It is highly desirable to facilitate the rapid changing of saddle members on a tube squaring tool that eliminates the need for special tools or disconnecting threaded members and the like while still providing a robust structure capable of securing tubular workpieces rigidly to the tube squaring tool during a machining operation.